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rick abath (voiceover): i was panicking. i didn't realize i was panicking, but i was completely panicking. i was afraid that they were going to set the place on fire after they were done. that was my fear. god, i hope they don't burn the place down. [suspenseful music] hello. and welcome to how it really happened. i'm jesse l. martin. boston's isabella stewart gardner museum is known for its vibrant art depicting picturesque dutch and renaissance scenes. but on one dark night in 1990, the museum became the scene of a horrifying crime. robbers swept in, terrorizing the guards,

and taking 13 works of art now worth half a billion dollars. the sinister smash and grab left the fbi with a mind boggling mystery on their hands. where are the missing masterpieces and who were the masterminds behind this audacious heist? this is how it really happened . [suspenseful music] kelly horan (voiceover): march 17th, 1990, is st. patrick's day, which is practically a national holiday in boston. randi kaye (voiceover): there are a lot of celebrations, a lot of parties. stephen kurkjian: the police are out en masse. every police officer who wears a uniform is on duty. but it was really what should have been a typical night at the gardner museum. stephen kurkjian (voiceover): there were two night watchmen the museum had in place.

randi kaye (voiceover): at 1:24 am, rick abath, one of the security guards, was at the security desk, and the buzzer went off. this is on palace road, which is the service entrance to the side of the museum. he answered it and saw two uniformed police officers standing outside. rick abath: i could see them on the outside camera. i thought they were just clearing drunks off the street. i just kind of leaned over to the intercom and said, yeah. and they said, boston police. we got a report of a disturbance on the premises. so he buzzed them in. randi kaye (voiceover): according to rick abath, the two men at the door were both white. one was tall, about 6'1". another one, he said, was shorter and wider. both had mustaches. he seemed to think that they were fake mustaches. they just looked like boston cops. rob fisher: right when they walk in,

they walk up to the security desk. they say, is there anybody else here. rick says, yes, there's another guard. stephen kurkjian (voiceover): the second guard, randy, was on the third floor. they said, well, can you call him down. so rick gets on the radio and asks randy to come down. and as soon as he was there, the cop that was dealing with me turned to me and said, don't i know you, don't i recognize you. i think there's a warrant out for your arrest. can you step out from behind the desk? so i came out from behind the desk. he said, up against the wall. and so, i put my hands up against the wall and he handcuffed me. there was one alarm called the panic button that you had to press if something went wrong. it was up on the underside of the desk, and that was the only alarm that went outside the museum. so by getting rick away from the panic button, there's now no way for either security guard

to send a signal of distress. randy and the other guard had never spoken to the press before. and chasing him down was quite a feat, but we went on the record. randy (voiceover): he told rick to stand against the wall and put his arms up. he does the pat down, he puts the cuffs on, and i'm just standing there with my jaw open. kelly horan (voiceover): randy's really worried. then the cops say, you too. and he's thinking, what did i do. randy (voiceover): i kept asking him over and over, why are we being arrested. why are we being arrested? and he wouldn't answer. very dramatically, he said, gentlemen, this is a robbery. and then all of a sudden, randy and rick are being led by these two men who they now realize are not real police officers to the basement of the museum.

they were both tied up. kelly horan (voiceover): rick was duct tape around his head. randi kaye (voiceover): it's very peculiar the way they were subdued. if you look at photos at the time, the duct tape is just wrapped right around the face, which is kind of strange. randy thought he was going to die. randy (voiceover): it was scary. and i remember feeling like i needed to prepare myself for death. [dramatic music] reporter: the isabella stewart gardner museum stands as it has for more than a century. within these walls is a remarkable private collection, some of the finest artwork ever created, much of it displayed here still according to the will of isabella stewart gardner. kelly horan (voiceover): isabella stewart gardner was dubbed by a boston newspaper of her time as one of the seven wonders of boston. it was the gilded age.

isabella was a boston socialite. kelly horan (voiceover): she had thought, as a young woman, that what boston really needed was art. and she began collecting voraciously. patricia vigderman (voiceover): titian's rape of europa, rembrandt's, in particular, the storm on the sea of galilee. she had a vermeer. kelly horan (voiceover): gardner herself prized the concert by vermeer possibly more than any other painting in her museum. this was a painting that she bought at auction in paris. she beat out the louvre museum. it's a masterpiece. kelly horan (voiceover): at some time, with this growing collection, she decided, well, this all belongs in a museum. patricia vigderman (voiceover): when she came to build it, she modeled it on a venetian palazzo. all the artwork goes up and down the walls. stephen kurkjian: when she opened the museum in 1903,

she mandated that it be free of charge to gain the appreciation and the attendance of all of boston. her museum at that point in time was the largest collection of art by a private individual in america. kelly horan (voiceover): august 21st, 1911, the mona lisa is found to be missing from the louvre museum in paris. immediately, isabella stewart gardner gives her guards a shoot to kill order. anybody tries to take anything from this museum, you shoot them dead. i think she would have been horrified to hear 80 something years later that neither security guard on duty that night wanted to risk their lives for her art. [suspenseful music]

rick abath: we talked about it a lot, how easy it would be to rob the museum. it seemed like a foregone conclusion. it was not at all inconceivable that the place could get robbed. once randy and rick were secured in the basement, the thieves made a beeline for the dutch room. up there, these scheming, cunning thieves turned into werewolves. the frames are broken, the glass is shattered.

kelly horan (voiceover): they took down storm the sea of galilee, enormous, rembrandt's only seascape, they took down lady and gentleman in black, also by rembrandt. they took down tiny postage stamp size rembrandt etching. randi kaye: they took vermeer's the concert, they took a piece of art by flinck called landscape with an obelisk, and then they take what's really called a chinese coup. but it's sort of a vase or an urn. stephen kurkjian (voiceover): then they moved to the short gallery. randi kaye: they took five degas sketches, and they also took a bronze eagle finial, which was part of a napoleonic flag. apparently, it seemed to investigators that they had tried to get the flag itself, but they weren't able to. so they took the finial off the flag. kelly horan (voiceover): also that night, manet's shay tortoni was taken. randi kaye (voiceover): the thieves didn't protect

the paintings in any way. they cut some of the artwork out of the frames. kelly horan: to even leave remnants of the painting behind was savage. in my mind, it's sort of like slashing someone's throat. today, the value of what was stolen, 13 pieces of art, is placed at more than $500 million, probably well above that. randi kaye (voiceover): the thieves didn't leave until sometime after 2:00 am, and they exited through the very same door that they came in. [suspenseful music] they tried to get buzzed in from that same employee entrance and nobody answered. they immediately see that things aren't right. there are no guards at the desk. they called the police. randi kaye (voiceover): police came, security came. shelley murphy (voiceover): the fbi was called in immediately.

they find the guards, luckily, alive and well in the basement. randi kaye (voiceover): and they saw what turned out to be the biggest art heist in history on their hands. reporter: where the artwork once hung is now just empty space inside this boston museum. reporter: paintings by vermeer, rembrandt, and others stolen. but so far, publicly at least, authorities have only these composite sketches to go on. kelly horan (voiceover): the thieves took the security camera tapes and they took the printouts of the motion detectors, which would have tracked where they were in all of their movements throughout the museum. kelly horan (voiceover): not knowing, however, that there is backup. so investigators were able to track their steps. rob fisher: there were fingerprints recovered in various points in the museum, whether on frames or on broken glass.

randi kaye (voiceover): but nothing that allowed investigators to link any of these fingerprints to a particular suspect. dna wasn't around at the time. and a lot of the forensic capability that exists, not even a fraction of it existed at the time. the security in museums at the time, it was almost primitive. so the investigators did what they could with what they had. i think initially, there was a lot of speculation, a belief that organized crime was involved. randi kaye (voiceover): there was talk of whitey bulger, who was one of boston's most notorious gangsters. could he have been involved? kelly horan: but if you're in boston on the morning of march 18th, 1990, and you hear that not one, not two, but three rembrandts have been stolen, you think of only one person. you think of myles connor. i collected art and antiques.

later on, i learned that it was not the hardest thing in the world to rob museums. myles connor-- he was a career criminal known for stealing art. he had stolen a rembrandt at one point. kelly horan: it was a rembrandt from the museum of fine arts. it was a very brazen daylight robbery. myles had a specially made oversized trench coat into which he could put a painting. it caught the attention of a guard who gave chase. and myles goes to the waiting van and they take off. so myles was the first person that we know the fbi looked at in the gardner heist. he would have been the number one suspect if not for the fact that he was in federal prison at the time. randi kaye (voiceover): so he couldn't have actually

been in the museum that night. but there was still a lot of questions about whether or not he orchestrated it. the feeling is if they don't explore all options to get the paintings back, they might be painting themselves into a corner. stephen kurkjian (voiceover): william youngworth had an antique shop. his importance in this case begins in 1997. reporter: william youngworth says he knows where the paintings are and will reveal it for a share of the $5 million reward. if i can produce on what they're asking for, then i deserve the reward like any other citizen would. randi kaye: he claimed that he had information about the missing artworks and that he could provide more information about them and maybe even access to them. youngworth somehow connected with a reporter from the boston herald, and they asked for proof. let's see the art. and the scheme that was arrived at was showing me a painting in its hidden location.

[suspenseful music] stephen kurkjian: tom mashberg was picked up at the herald on 11 o'clock at night, and they drove to brooklyn. they went up to a warehouse and there is a container with several large roll-up cylindrical tubes. and youngworth takes a canvas out of the bin and holds it over his head and lets the canvas roll down. randi kaye (voiceover): this reporter thought what he saw was storm on the sea of galilee, one of the missing rembrandts. and the herald was thrilled. ran with the story. the big headline, "we've seen it." but had they really?

and they're all coming? those who are still with us, yes. grandpa! what's this? your wings. light 'em up! gentlemen, it's a beautiful... ...day to fly.

c music] reporter: boston's isabella stewart gardner museum is an intimate showcase of some of the finest works of art. but it's perhaps best known for what was stolen. william youngworth, who has a rap sheet of some 60 convictions, claims to know where the gardner art is. [suspenseful music] randi kaye: william youngworth got in touch with a reporter from the boston herald.

youngworth took this reporter to a warehouse of sorts. and this reporter was shown a storm on the sea of galilee. stephen kurkjian (voiceover): he only showed for a flash of a second. shortly thereafter, i was also given photographs and paint chips which purported to be indicative of the real art. shelley murphy: as soon as the fbi sent the paint chips to its lab for analysis, they concluded that these were not from the storm on sea of galilee, and they just stopped all negotiations with youngworth. it all comes to nothing for the museum. randi kaye (voiceover): the fbi was getting so many tips. but then it went silent. even though there were these 13 works of art that were missing, the information just dried up, until 2005 when the fbi got a big tip. interviewer: recently, you took a trip to france in tracking down potential evidence in this case.

you can confirm that you did go? yes, we did go to france. i can't get specific on what we were doing over there. but in broad terms, i can tell you that we were covering yet another lead that's come up. randi kaye: around 2005-2006, the fbi gets a big tip that two frenchmen living in miami are trying to broker a deal regarding two paintings, a rembrandt and vermeer. what was really interesting about that statement, the vermeer-- there is only 34 verifiable vermeers in the world. and the only one that was missing at that time is the concert that was stolen from the gardner museum. [suspenseful music] randi kaye (voiceover): bob wittman is an undercover agent with the art heist unit for the fbi. it was formed after the theft at the gardner museum. so bob wittman goes undercover as an art buyer. i was acting as a shady dealer, so to speak, who was representing clients around the united states who had a lot of money, and they would

be very interested in buying stolen artworks. we were able to make an arrangement to go meet with these people in miami. bob wittman really gets in close undercover with two criminals, sonny and loronze. bob wittman: so sonny was working with groups that stole paintings. he had information about two paintings that had been stolen from the united states back in the early '90s, late '80s. bob wittman is told that the two paintings are in the hands of corsican mobsters. corsica is an island in the mediterranean. and it's a french territory. what's interesting is that this finial was stolen from an napoleonic flag the night of the robbery. it was sort of an odd choice for the thieves to take. but it turns out that corsica is essentially the homeland of napoleon. kelly horan: it's a very compelling notion

that a corsican band of gangsters might have tried to steal back their flag and pull off the entire rest of the heist in the process. bob wittman: so sonny said that he had access to these paintings. they were in the south of france. and he told me that they wanted $30 million for the two paintings. so we started the investigation. at that point, we called it operation masterpiece. and this was an undercover operation to try to do a buy bust to get these two paintings back to the united states. we contacted the ocbc, which is the french art crime team in paris. they became our partners in the investigation. and they set up wiretaps, and listening in, and they heard sonny using a code. they were talking about the rembrandt and the vermeer being streets. so the idea was my person in the united states wants to buy something from rembrandt street

or vermeer street. and that was the code they were using, thinking that no one could figure out what they were saying. [suspenseful music] sonny said that they had four paintings. these paintings had all been stolen in an armed robbery for the museum of fine arts in nice, france. so sonny said we needed to buy those first. so we set up a meeting in marseille. they brought the paintings and they were arrested. all four paintings were recovered, but my cover was shot. they knew not to try to sell any more paintings to bob, the dealer from the united states. the whole operation falls apart. bob wittman (voiceover): and as a result of my cover being blown, the leads vanished. there was a lot of time and energy spent

on investigating whether the paintings were in or could be in southern france. could that be a viable theory? i think it would have been difficult to get these paintings out of the country and over there. if you had a professional crew that was going to be able to get them to a foreign country in europe, they probably would have got more than 13 pieces and gotten them over to europe right away. but i could be totally wrong. [suspenseful music]

how it really happened. art selling for millions of dollars used to be unheard of. but then in the '70s and '80s, for more people, art became an asset and prices skyrocketed. van gogh's irises shattered auction records in 1987, going for $53.9 million. suddenly, everyone, including criminals, wanted to get their hands on big name pieces. all of that set the stage for what happened in boston's gardner museum in 1990. bob wittman: in the gardner case, it's really interesting because three of the pieces that were stolen were rembrandt's. one of the rembrandts that was taken was an etching. not worth a whole lot of money. the other two were very, very valuable. the storm over the sea of galilee is the only seascape rembrandt ever did. so in some respects, you could almost think that they were targeted.

what is so intriguing about this is if in fact someone went in there to steal rembrandt, why are they stealing a coup like a chinese beak, right? why are they stealing sketches of jockeys on horses? in the majority of major art heists, thieves go to a museum looking for big name well-known artists because of the value ascribed to such art. rob fisher: the gardner heist doesn't really fit a profile of your typical art robbery. and if you had the means to pull this robbery off, you would have hired a professional crew, somebody who understood how to handle this art. i think from all the evidence we've seen, this crew didn't know how to handle this art. i can't imagine some rich collector of fine art would be happy they were cut out of the frames and damaged. at the fbi, we found about 89% of museum and institutional heists are inside jobs.

that's how these things get stolen. when you look at the gardner heist, you can't help but wonder if this was some sort of inside job. robert sikellis (voiceover): first and foremost was the fact that the robbers knew that they had to pull the guard out of the booth because that's where there was panic buttons. and we know that the thieves were in the museum for 81 minutes. 81 minutes is an awful long time. a robbery like this, seemingly without a care, suggests to me that they were very, very comfortable that they had a good understanding of how the security system works, how the police could be notified, and that no one had been notified. shelley murphy: another thing is that where the storm on the sea of galilee was hanging, there was a secret door. it was a jar that thieves knew about that door. rob fisher: the robbers also, before they left, they did have access to the guard supervisor's office. and that's where there was a vhs system that was recording what was happening on the security cameras. the way that system worked, it was a 24 hour loop tape for every day of the week.

and they must have known that because if they took the vhs tape for the night of the robbery. i will tell you that to find it does speak to some-- maybe some insider information, not necessarily complicity, but just information. rick abath: i knew there obviously have to be looking at me as a suspect. i'm the guy who opened the door. i assumed that i was a suspect. stephen kurkjian: the responsibility of the two night watchmen was one was to stay at the security desk and one was to do touring the galleries. so that night, rick had done the first tour and randy had been at the desk. rick abath: there were motion detectors. and so, while one person was walking through the museum, they'd be setting off the motion detector alarms and stuff like that. kelly horan: edouard manet's painting, shay tortoni, was in a room called the blue room at the museum on the first floor. it was about 8 by 10 and it was in a gold gilded frame, and it was here. and they didn't take the frame.

they left the frame behind. - they left the frame behind. and it was curious because all of the frames were left behind in the room from which the paintings were taken, except this one. this frame was left in the security director's chair. this part of the theft is different from the rest of it. kelly horan (voiceover): when you look at the motion sensor readouts from the night of the theft-- the motion sensors do not show the thieves steps on the first floor of the museum. there's no activity in that room. the only person we know to have stepped into that room is rick abath. rick went through the room on his tour of the gallery at midnight, an hour before the bad guys show up. randi kaye: so how was that manet removed from the blue room did it happen earlier in the night when only the guards were in the museum? this casts a lot of suspicion on one person. [suspenseful music] once i say-- you know, sat down with the fbi, i think the first thing i said was, what do you want to know? and there's one more thing we know, which we learned many years after the heist-- randi kaye: the night of the heist at the gardner museum,

rick abath was coming down to take over at the security guard desk and let his partner then go do his rounds in the museum. but before he did that, he went over to that door that the thieves came through. and he opened and closed the door before taking his seat at the desk. and i questioned rick about it. and he said that he did it because he wanted to make sure the door was locked. kelly horan (voiceover): why would he have done that? that was not part of his rounds, that was not part of the typical security protocol? i thought it was unusual. the supposition has been that he was signaling the thieves who were waiting outside. rob fisher: rick said, well, i did that every night. i was trained to do it that way. i'm not sure why you would open an outside locked door a little past 1 o'clock in the morning shortly before, coincidentally, two robbers show up. kelly horan: rob fisher wants to know, ok, if you say that this was what you did as a matter of course, show me the tape from the night before.

if what i see there is rick abath opening the closing the door, i will believe him. and that'll be good enough for me. rob fisher: it was a 24 hour loop system. there were seven tapes. it didn't appear anybody had focused on those. [dramatic music]

seen video, a man who may have pulled off the biggest art heist in history. take a good look. the grainy video is from march 17th, 1990, the night before, two men broke into boston's isabella stewart gardner museum. [suspenseful music]

what we now know, the person rick abath led in the night before was the deputy director of security at the gardner museum, who reportedly had left his wallet at the museum. interviewer: was it ruled out that the guards didn't have anything to do with this? i can't really say. i can tell you that the guards are no longer considered suspects at this point. rick abath has always said that he had nothing to do with this heist. rob fisher (voiceover): rick has never been charged. if you look at how he lived his life subsequent to the heist, he led a quiet life. he led a simple life. he certainly didn't lead the kind of life that you would attribute to someone who could have been involved in the greatest art heist of all time. [suspenseful music] about four miles from the gardner museum is trc auto electric. you would just think it's a place where you go to have your car repaired.

what turns out to be is the nucleus for a criminal organization. the fbi, for years, had been looking at this group that hung out at trc auto. one of the guys who ran the shop, his name was carmelo merlino. carmelo merlino doesn't know anything about fixing cars, but he was very skilled at planning heists, and selling drugs, and he's got a whole network of criminals under him. he stood out as a real person of interest, as did his two underlings, david turner and stephen rossetti. robert sikellis: this was an extraordinarily dangerous group. they'd been involved in armed robberies. so we were on investigation wholly unrelated to preceding the gardner heist of this group. i had an informant that confided his suspicions of who might have been involved in this particular robbery. and his suspicions were carmelo merlino, david turner, stephen rossetti.

rossetti and turner, supposedly they were home invaders. they would crash into a house of a person who was rich, tie them up, get the money and leave. that's kind of like what happened there at the museum. it wouldn't surprise me at all if they had been involved. robert sikellis: in one surveillance, we saw david turner taking a vase, a chinese ming vase out of his car and brought into his lawyer's office. then we started to suspect, could it possibly have something to do with the museum. if you look at one of the sketches by the guards, it has a resemblance to david turner. carmelo merlino, david turner, and stephen rossetti were all arrested by me and my squad when they were coming together to rob a vault facility. we took them all in to the office after the arrest, and i interviewed them individually. and the first thing i asked them about was the gardner

and whether they were involved in it. and all three of them completely denied any knowledge of that crime. shelley murphy: some of these people went to prison for a long time. are you really going to die in prison and spend years in prison if you know where the rembrandt is? i don't think so. bob wittman (voiceover): well, one of the other things that led us to thinking maybe there's a connection here-- if you look at one of the sketches by the guards, one has a resemblance to david turner. and the other one has a resemblance to george reissfelder, who was one of the other individuals that was part of this trc gang. not only is he a dead ringer, curiously close to the first anniversary of the heist in 1991, he turns up dead, and it's a cocaine overdose, but it was injected. and various people close to george said, he didn't inject. he was afraid of needles.

it raises a question, was reissfelder murdered. his name is floated as a suspect in the gardner heist. and his brother, after george's death, really wants to clear his name. his brother comes to anthony morais, head of security at the gardner. and anthony says, have a look at some of the paintings that were stolen. have you seen any of these? he goes down through the line of the 11 pieces. when he gets to shay tortoni, george reissfelder's brother jumps in his seat and he says, i've seen that. my brother had that painting. they go to reissfelder's apartment. there's no manet in that apartment. shelley murphy: merlino had been at the house right around when reissfelder died. did merlino take the painting off the wall after he died? there were just so many questions, but unresolved.

[suspenseful music] randi kaye (voiceover): and the fbi said that they were going to make a big announcement. something's here, something's breaking. with today's announcement, we begin the final chapter. the fbi tells us they now know who the thieves are. [dramatic music]

ok, good afternoon, everybody. great to have each of you here today. my name is rick deslauriers, and i'm the special agent in charge of the fbi's boston division. on march 18th, 2013, the fbi said that they were going to hold a press conference and make a big announcement. 23 years ago, 13 culturally significant pieces of art were stolen from boston's isabella stewart gardner museum. we are pleased to announce the fbi has made significant investigative progress in the search for the stolen art. they announced, they believed they had solved it. it's the first break in years. shelley murphy (voiceover): they were confident they knew the identities of the thieves. stephen kurkjian: two thieves, but they're both dead. and the fbi have decided, for investigative reasons, not to make their identities known. and they say, we can tell you with a reasonable degree of certainty that these paintings, these stolen artworks, traveled from boston through connecticut to philadelphia.

geoffrey kelly: about a dozen years ago, at least a number of these paintings were offered for sale down in the philadelphia area. and we don't know whether these paintings were actually-- whether the deal was consummated, if they left the philadelphia area, and where they are now. [suspenseful music] we had a significant break in the case a few years ago when we developed some information as to who was actually responsible for the heist. david turner, from trc auto, ended up getting years shaved off his sentence, fueling the belief that he had provided some information. do you have any knowledge of the gardner heist? please get away from me. robert sikellis: the reduction took place in 2013. what i think happened there is that turner gave him the details of what happened in the steps up until what he knew. [suspenseful music] the prime theory is that it was local sort of petty criminals that committed the heist. my reporting on it would say the thief is bobby donati.

bobby donati was this sort of what i would characterize as a mob associate, notorious art thief. myles connor has said bobby donati did it. we went there on several occasions and went through the place, sat outside the place, got an idea of the comings and goings and the security within the place. bobby donati and myles-- myles told me, went to the gardner museum and kind of cased the place. interviewer: you thought the security was fairly lax at the time-- - yes. and i felt that it was a target that could be taken down. kelly horan: myles claims that as they walked through, myles said, what would you take if you could? and donati really liked the finial. we felt that they would come up with a substantial amount of money to get them back. and i went away to federal prison. initially, the plan, as it happened, was my plan,

was my friends that did it. stephen kurkjian (voiceover): and then bobby donati gives the art to his great friend, bobby guarente. bobby guarente claims to be a made man with the philadelphia mafia. shelley murphy (voiceover): guarente, who was very well known and had a lot of ties to different people, had ties to david turner. he was very good friends with carmelo merlino. guarente in my view was behind a lot of this. and i think he was the one that was going to be the middleman. the paintings were going to go to him. for selling, does donati give all of them? i'm not sure. but some of them. after bobby guarente died, his wife told the fbi, oh, yes, he had at least two of the gardner museum stolen paintings and that he gave them, before he died, to a man named bobby, bobby gentile. so now the focus shifts to bobby gentile.

a dramatic search in connecticut linked to one of the greatest unsolved art heists ever. the fbi have raided 75-year-old robert gentile's home in connecticut. [suspenseful music] bobby gentile is a connecticut criminal with connections to mob groups and other criminal enterprises. they have ground penetrating radar. they have a few bloodhounds. they've got a ferret back there. they got everything that you could possibly use to try to find what they're looking for. they searched gentile's house and came up with a couple of pieces of evidence that are suspicious. they find police caps. they also find a boston herald from the day after the heist. inside is a handwritten list of all the pieces of art that were stolen with prices-- stephen kurkjian (voiceover): they get a tip that it's maybe in the shed in his back yard.

[intense music] under the shed, there were some type of secret compartment. and they thought, maybe this was it. there was a huge kind of plastic, oversized, tupperware thing, which would have been ideal place to hide the paintings. randi kaye (voiceover): but when they opened it, there was nothing there. stephen kurkjian: after my interviewing gentile, he said, no artwork? and he said, no. i had nothing to do with it. a lie? who knows. reporter: they say they turned up four guns, ammo, homemade dynamite, a stun gun, $20,000 stuffed into a grandfather clock with a set of brass knuckles. but they did not find any stolen art. the artworks were not there. doesn't mean they were never there. that's the key. but they weren't there when the fbi finally searched that house. looking for stolen art is sort of like trying to find, in this case, 13 needles in a haystack. randi kaye (voiceover): i don't know if we're ever going to find out where these paintings are.

i can't believe that in boston, we haven't figured it out already. bob wittman: it might take 30 or 40 years to recover these pieces. the oldest case i ever had involved an original copy of the bill of rights that was stolen in 1865 by a union trooper. and we were able to recover that from the state of north carolina in 2003. so it was 138 years that it was missing. kelly horan: every single person you talk to has their own theory. they're in a basement, they're in an attic, they're under a bed, they're in europe. everybody will tell you something different because nobody knows. bob wittman: as an investigator doing these cases for 30 years, i think the art is in different places. i don't think all 13 pieces are still in one spot. but then again, i could be wrong because, you know, we don't know. they might all be sitting in an attic two blocks from the museum. it's certainly something that haunts everybody who attaches themself in some way. this became so much more than an assignment for me.

this became a complete obsession. to this day, my 17-year-old son uses against me to say, why should i listen to you, you couldn't even find the paintings. [laughs] [upbeat music] the statute of limitations on the gardner museum robbery has expired. and prosecutors have said, they'd be willing to make a deal with anyone who steps forward in possession of the stolen art. look in your attics, search the flea markets. and if you know anything about the whereabouts of the 13 pieces, call the fbi at 1800-call-fbi. the current reward for information that leads to the recovery of the paintings is $10 million. i'm jesse l. martin. thanks for watching. good night.